RESUMO
BACKGROUND AND PURPOSE: Catheter-related blood circulation infection is the most dangerous and serious side-effects of vascular catheters, which leads to the enhancement of the costs, mortality, and hospital stay duration, especially in the Intensive Care Unit. Regarding this, the aim of the current study was to identify the prevalence of catheter-induced candidemia in the Tehran Heart Center, a heart hospital in Tehran, Iran. MATERIALS AND METHODS: This study was conducted on patients admitted to Tehran Heart Center for a minimum of 7 days during 18 months. To detect the fungal elements, blood culture and catheter culture were performed in the patients receiving central or peripheral venous catheter. Then, the polymerase chain reaction (PCR) was applied to determine the possible diagnosis. RESULTS: The investigation of 223 samples led to the identification of a total of 15 (6.7%) yeast isolates obtained from 9 (60%), 4 (26.6 %), and 2 (13.4%) catheter, blood, and skin (of the catheter insertion areas) cultures, respectively. Out of nine Candida isolates obtained from the catheter samples, 1 (11.1%), 1 (11.1%), 2 (22.2%), and 5 (55.6%) cases were identified as C. tropicalis, C. membranifaciens, C. glabrata, and C. albicans, respectively, using the internal transcribed spacer region sequencing. Furthermore, the four yeasts isolated from the blood culture included C. tropicalis, C. carpophila, C. membranifaciens, and Cryptococcus albidus. Additionally, one case of C. glabrata and one case of C. albicans were isolated from the skin culture of the catheter insertion areas in patients with positive catheter culture. We reported two cases of catheter-related candidemia caused by C. membranifaciens and C. tropicalis on the basis of the genetic similarity of the species isolated from the blood and catheter. These cases were treated successfully with intravenous fluconazole and catheter removal. CONCLUSION: There is some evidence indicating the growing prevalence of non-albicans Candida infections. Many risk factors, including prior antibiotic therapy, use of a central venous catheter, surgery, and parenteral nutrition, are considered to be associated with candidemia in hospitalized heart failure patients. The identification of the route of infection in candidemia is difficult. In the current study, the positive blood and catheter cultures for Candida isolates and the similarity of the ITS region of ribosomal DNA sequence of Candida isolated from two patients confirmed the diagnosis of intravenous catheter-related candidemia.
RESUMO
The incidence of candidemia due to the uncommon non-albicans Candida species appears to be increasing, and certain species such as Candida (C.) membranaefaciens have been reported in some clinical researches. Vascular catheters are considered the likely culprit for the sudden emergence of hospital-acquired candidemia. The identification of C. membranaefaciens can be problematic in clinical practice owing to its phenotypic resemblance to C. guilliermondii. We report the first case of C. membranaefaciens in Iran, which occurred in a 70-year-old woman, who had coronary artery bypass grafting (CABG). We isolated germ-tube negative yeast from both blood culture and central venous catheter (CVC) tip culture on brain-heart infusion agar, Sabouraud dextrose agar plates, and biphasic brain-heart infusion media bottle; it developed smooth, pink colonies on CHROMagar Candida. By using the polymerase chain reaction and sequencing of theinternal transcribed spacer region of rDNA, we identified C. membranaefaciens. After the removal of the CVC and initiation of Fluconazole treatment, the patient's condition gradually improved and she was discharged from the hospital. The early detection of organisms in the catheter, removal of the catheter, and treatment with anti-fungal antibiotics have an important role in controlling disease and preventing septicemia after CABG. As C. membranaefaciens is an opportunistic Candida species, both clinicians and microbiologists should be aware of the factors that confer fast diagnosis and appropriate treatment.
